The army will have to intervene to prevent further fighting. 2 [ intransitive, transitive] to interrupt someone when they are speaking ‘Stop shouting, Emily, ’ John intervened. 3 [ intransitive] if an event intervenes, it delays or interrupts something else He was just establishing his career when the war intervened. 4 [ intransitive] if a period of time intervenes, it comes between two events In the six years that intervened,...